09 June 2008

In the dense fog that passes for the national climate policy debate, the major players stumble from one lamp-post to the next, unable to see the bigger picture in the murky light.
Devoid of context, their climate view is so constrained that they fail to identify the core problem: that the world stands on the edge of a precipice beyond which human actions will be no longer able to control in any meaningful way the trajectory of the climate system, or the fate of human life in a rapidly degrading natural world.
There is no clearer example than the fate of the Arctic.
More than 80% of the mass of sea-ice in the Arctic Ocean in summer has already been lost. An area of summer sea-ice once as large as Australia is rapidly disintegrating, with consequences that will reverberate around the globe.
Scientists with expertise on the Arctic environment are predicting that the Arctic Ocean will be ice free in summer between 2010 and 2013, and that once lost, the Arctic summer sea-ice will not return. Here's what they are saying:

The frightening models [of Arctic sea-ice loss] we didn't even dare to talk about before are now proving to be true.’ According to these models, there will be no sea ice left in the summer in the Arctic Ocean somewhere between 2010 and 2015. ‘And it's probably going to happen even faster than that.’ — Louis Fortier, scientific director of the Canadian research network ArcticNet .

‘Our projection of 2013 for the removal of ice in summer is not accounting for the last two minima, in 2005 and 2007… So given that fact, you can argue that may be our projection of 2013 is already too conservative’ — Professor WieslawMaslowski, Naval Postgraduate School, California

‘I think the tipping point for perennial sea-ice has already passed… It looks like [it] will continue to decline and there’s no hope for it to recover’ in the near period. — Dr JosefinoComiso, senior research scientist, NASA Goddard Space Centre

‘The Arctic is often cited as the canary in the coal mine for climate warming… and now as a sign of climate warming, the canary has died.” — Dr Jay Zwally, glaciologist, NASA Goddard Space Flight Center

The loss of the Arctic summer sea-ice will cause a large local warming in the Arctic region of around 5ºC and a smaller but very significant global warming of around 0.3ºC .
This further warming of the Arctic will significantly add to the speed of disintegration of the Greenland ice sheet (sea-level rise of 7 metres if fully lost, possibly five metres this century according to NASA climate chief Dr James Hansen) and to the rate of permafrost melting, which will release much more carbon dioxide and methane and further drive up global warming.
I are not aware of any well-informed climate scientist who thinks that it is possible to have a safe climate or avoid dangerous climate change with the permanent loss of the Arctic summer sea-ice. This topic is not being addressed in Australia, though it must frame the whole debate. To not consider the Arctic is to ignore the biggest issue today in global warming.
Because of the dangerous knock-on effects caused by its loss, the Arctic sea ice must be restored to its normal extent as fast as possible.
To get the Arctic sea ice back we need to cool the earth by about 0.3ºC. If we don’t, we cannot avoid very dangerous climate impacts. There is no third way. This is the new very inconvenient truth politicians seek to avoid.
To cool the earth fast enough to get the Arctic sea-ice back quickly, we need to move to zero greenhouse gas emissions as fast as the economy can be restructured, and is environmentally safe to do so, and take about 200 billion tonnes of carbon dioxide out of the air. We also need to find environmentally-safe mechanisms to actively cool the earth while navigating this transition.
Taken together this is a staggering task in terms of the necessary scale and speed of action, but there is simply no alternative if we are to avoid catastrophic climate change.
The bottom line is that we cannot leave the Arctic ice-free in summer and avoid climate catastrophe. This is the elephant in the room that politicians strain to avoid. It is not being talked out honestly.
Politicians can ignore or downplay the challenge of the Arctic, only by playing dice with our future and that of future generations.